A "house" is essentially a container -- for a person, a family, several families or even a large group with shared interests (think of the term "houses of worship.") In the Bible, a "house" is also a container, but for spiritual things rather than natural things. In various uses a "house" can represent part of the mind, the whole mind, a whole person or even a church. The other nuance to the word "house" is that it is generally used in regards to our affections and desires rather than our thoughts and principles. This makes sense; we tend to engage our thoughts and rationality when we are out in the world doing our work, but when we are inside our houses we are driven most by love for our families and the desire to be good to those we love. So "house" tends to represent the things we want and care about -- which are ultimately the things that define us.

711. That 'entering into the ark' means being made ready has been stated already at verse 18 of the previous chapter. There however it meant being made ready for salvation as regards things of the understanding, which are the truths of faith, whereas here it means being made ready as regards those of the will, which are goods springing from charity. Unless a person has been made ready, that is, has been supplied with truths and goods, he cannot possibly be regenerated, still less undergo temptations, for the evil spirits who are at that time with him activate the falsities and evils that are his. And unless truths and goods are present towards which they are turned by the Lord and by which they are scattered, he goes under. The truths and goods are the remnants which the Lord preserves for such purposes.